Pacific Digital U-30201 DVD±RW recorder - Page 9

Writing Quality Tests - 3T Jitter Tests

On 80min 48X CD-R disc media from Taiyo Yuden we burned the same AudioCD project at 8x, 16x, 24x and 40x. The 3T Pit & Land Jitter graphs are presented here.

- 3T Pit results

The drive introduced high 3T pit jitter levels (i.e. above 35ns) with the specific media at all speeds. In general, there doesn't appear to be a speed that is more ideal than another. For example, at 40x while it is almost always above the 35nsec level, it doesn't exceed it by much and remains fairly constant, whereas at 24x it begins quite low and towards the end reaches 45nsec, which was also the highest level reached.

The average 3T Pit Jitter values for all recording speeds are illustrated in the following table.

- 3T Land results

Land jitter on the other hand was very good with the exception being 40x which was the only speed to go above the Red Book limit of 35nsec. At all other speeds, the jitter was well within limits.

The average jitter for all speeds presented in the graph below show that the land jitter values w.

- Summary

The Pacific Digital U-30201 did not return good jitter values or at least not as good as we would have expected, considering that the LiteOn drive for the same set of tests was particularly good. The table above further shows that the drive did go over the 35nsec Red Book limit for all speeds excepting 8x.

The following page where we check the jitter levels produced on various manufacturers discs, should give a better indication of the writing quality level of the drive.